xref: /openbmc/linux/net/sctp/stream.c (revision 4cff79e9)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001 Intel Corp.
6  *
7  * This file is part of the SCTP kernel implementation
8  *
9  * This file contains sctp stream maniuplation primitives and helpers.
10  *
11  * This SCTP implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * This SCTP implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, see
25  * <http://www.gnu.org/licenses/>.
26  *
27  * Please send any bug reports or fixes you make to the
28  * email address(es):
29  *    lksctp developers <linux-sctp@vger.kernel.org>
30  *
31  * Written or modified by:
32  *    Xin Long <lucien.xin@gmail.com>
33  */
34 
35 #include <linux/list.h>
36 #include <net/sctp/sctp.h>
37 #include <net/sctp/sm.h>
38 #include <net/sctp/stream_sched.h>
39 
40 /* Migrates chunks from stream queues to new stream queues if needed,
41  * but not across associations. Also, removes those chunks to streams
42  * higher than the new max.
43  */
44 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
45 				     struct sctp_stream *new, __u16 outcnt)
46 {
47 	struct sctp_association *asoc;
48 	struct sctp_chunk *ch, *temp;
49 	struct sctp_outq *outq;
50 	int i;
51 
52 	asoc = container_of(stream, struct sctp_association, stream);
53 	outq = &asoc->outqueue;
54 
55 	list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
56 		__u16 sid = sctp_chunk_stream_no(ch);
57 
58 		if (sid < outcnt)
59 			continue;
60 
61 		sctp_sched_dequeue_common(outq, ch);
62 		/* No need to call dequeue_done here because
63 		 * the chunks are not scheduled by now.
64 		 */
65 
66 		/* Mark as failed send. */
67 		sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
68 		if (asoc->peer.prsctp_capable &&
69 		    SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
70 			asoc->sent_cnt_removable--;
71 
72 		sctp_chunk_free(ch);
73 	}
74 
75 	if (new) {
76 		/* Here we actually move the old ext stuff into the new
77 		 * buffer, because we want to keep it. Then
78 		 * sctp_stream_update will swap ->out pointers.
79 		 */
80 		for (i = 0; i < outcnt; i++) {
81 			kfree(new->out[i].ext);
82 			new->out[i].ext = stream->out[i].ext;
83 			stream->out[i].ext = NULL;
84 		}
85 	}
86 
87 	for (i = outcnt; i < stream->outcnt; i++)
88 		kfree(stream->out[i].ext);
89 }
90 
91 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
92 				 gfp_t gfp)
93 {
94 	struct sctp_stream_out *out;
95 
96 	out = kmalloc_array(outcnt, sizeof(*out), gfp);
97 	if (!out)
98 		return -ENOMEM;
99 
100 	if (stream->out) {
101 		memcpy(out, stream->out, min(outcnt, stream->outcnt) *
102 					 sizeof(*out));
103 		kfree(stream->out);
104 	}
105 
106 	if (outcnt > stream->outcnt)
107 		memset(out + stream->outcnt, 0,
108 		       (outcnt - stream->outcnt) * sizeof(*out));
109 
110 	stream->out = out;
111 
112 	return 0;
113 }
114 
115 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
116 				gfp_t gfp)
117 {
118 	struct sctp_stream_in *in;
119 
120 	in = kmalloc_array(incnt, sizeof(*stream->in), gfp);
121 
122 	if (!in)
123 		return -ENOMEM;
124 
125 	if (stream->in) {
126 		memcpy(in, stream->in, min(incnt, stream->incnt) *
127 				       sizeof(*in));
128 		kfree(stream->in);
129 	}
130 
131 	if (incnt > stream->incnt)
132 		memset(in + stream->incnt, 0,
133 		       (incnt - stream->incnt) * sizeof(*in));
134 
135 	stream->in = in;
136 
137 	return 0;
138 }
139 
140 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
141 		     gfp_t gfp)
142 {
143 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
144 	int i, ret = 0;
145 
146 	gfp |= __GFP_NOWARN;
147 
148 	/* Initial stream->out size may be very big, so free it and alloc
149 	 * a new one with new outcnt to save memory if needed.
150 	 */
151 	if (outcnt == stream->outcnt)
152 		goto in;
153 
154 	/* Filter out chunks queued on streams that won't exist anymore */
155 	sched->unsched_all(stream);
156 	sctp_stream_outq_migrate(stream, NULL, outcnt);
157 	sched->sched_all(stream);
158 
159 	ret = sctp_stream_alloc_out(stream, outcnt, gfp);
160 	if (ret)
161 		goto out;
162 
163 	stream->outcnt = outcnt;
164 	for (i = 0; i < stream->outcnt; i++)
165 		stream->out[i].state = SCTP_STREAM_OPEN;
166 
167 	sched->init(stream);
168 
169 in:
170 	sctp_stream_interleave_init(stream);
171 	if (!incnt)
172 		goto out;
173 
174 	ret = sctp_stream_alloc_in(stream, incnt, gfp);
175 	if (ret) {
176 		sched->free(stream);
177 		kfree(stream->out);
178 		stream->out = NULL;
179 		stream->outcnt = 0;
180 		goto out;
181 	}
182 
183 	stream->incnt = incnt;
184 
185 out:
186 	return ret;
187 }
188 
189 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
190 {
191 	struct sctp_stream_out_ext *soute;
192 
193 	soute = kzalloc(sizeof(*soute), GFP_KERNEL);
194 	if (!soute)
195 		return -ENOMEM;
196 	stream->out[sid].ext = soute;
197 
198 	return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
199 }
200 
201 void sctp_stream_free(struct sctp_stream *stream)
202 {
203 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
204 	int i;
205 
206 	sched->free(stream);
207 	for (i = 0; i < stream->outcnt; i++)
208 		kfree(stream->out[i].ext);
209 	kfree(stream->out);
210 	kfree(stream->in);
211 }
212 
213 void sctp_stream_clear(struct sctp_stream *stream)
214 {
215 	int i;
216 
217 	for (i = 0; i < stream->outcnt; i++) {
218 		stream->out[i].mid = 0;
219 		stream->out[i].mid_uo = 0;
220 	}
221 
222 	for (i = 0; i < stream->incnt; i++)
223 		stream->in[i].mid = 0;
224 }
225 
226 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
227 {
228 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
229 
230 	sched->unsched_all(stream);
231 	sctp_stream_outq_migrate(stream, new, new->outcnt);
232 	sctp_stream_free(stream);
233 
234 	stream->out = new->out;
235 	stream->in  = new->in;
236 	stream->outcnt = new->outcnt;
237 	stream->incnt  = new->incnt;
238 
239 	sched->sched_all(stream);
240 
241 	new->out = NULL;
242 	new->in  = NULL;
243 	new->outcnt = 0;
244 	new->incnt  = 0;
245 }
246 
247 static int sctp_send_reconf(struct sctp_association *asoc,
248 			    struct sctp_chunk *chunk)
249 {
250 	struct net *net = sock_net(asoc->base.sk);
251 	int retval = 0;
252 
253 	retval = sctp_primitive_RECONF(net, asoc, chunk);
254 	if (retval)
255 		sctp_chunk_free(chunk);
256 
257 	return retval;
258 }
259 
260 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
261 				      __u16 str_nums, __be16 *str_list)
262 {
263 	struct sctp_association *asoc;
264 	__u16 i;
265 
266 	asoc = container_of(stream, struct sctp_association, stream);
267 	if (!asoc->outqueue.out_qlen)
268 		return true;
269 
270 	if (!str_nums)
271 		return false;
272 
273 	for (i = 0; i < str_nums; i++) {
274 		__u16 sid = ntohs(str_list[i]);
275 
276 		if (stream->out[sid].ext &&
277 		    !list_empty(&stream->out[sid].ext->outq))
278 			return false;
279 	}
280 
281 	return true;
282 }
283 
284 int sctp_send_reset_streams(struct sctp_association *asoc,
285 			    struct sctp_reset_streams *params)
286 {
287 	struct sctp_stream *stream = &asoc->stream;
288 	__u16 i, str_nums, *str_list;
289 	struct sctp_chunk *chunk;
290 	int retval = -EINVAL;
291 	__be16 *nstr_list;
292 	bool out, in;
293 
294 	if (!asoc->peer.reconf_capable ||
295 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
296 		retval = -ENOPROTOOPT;
297 		goto out;
298 	}
299 
300 	if (asoc->strreset_outstanding) {
301 		retval = -EINPROGRESS;
302 		goto out;
303 	}
304 
305 	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
306 	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
307 	if (!out && !in)
308 		goto out;
309 
310 	str_nums = params->srs_number_streams;
311 	str_list = params->srs_stream_list;
312 	if (str_nums) {
313 		int param_len = 0;
314 
315 		if (out) {
316 			for (i = 0; i < str_nums; i++)
317 				if (str_list[i] >= stream->outcnt)
318 					goto out;
319 
320 			param_len = str_nums * sizeof(__u16) +
321 				    sizeof(struct sctp_strreset_outreq);
322 		}
323 
324 		if (in) {
325 			for (i = 0; i < str_nums; i++)
326 				if (str_list[i] >= stream->incnt)
327 					goto out;
328 
329 			param_len += str_nums * sizeof(__u16) +
330 				     sizeof(struct sctp_strreset_inreq);
331 		}
332 
333 		if (param_len > SCTP_MAX_CHUNK_LEN -
334 				sizeof(struct sctp_reconf_chunk))
335 			goto out;
336 	}
337 
338 	nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
339 	if (!nstr_list) {
340 		retval = -ENOMEM;
341 		goto out;
342 	}
343 
344 	for (i = 0; i < str_nums; i++)
345 		nstr_list[i] = htons(str_list[i]);
346 
347 	if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
348 		retval = -EAGAIN;
349 		goto out;
350 	}
351 
352 	chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
353 
354 	kfree(nstr_list);
355 
356 	if (!chunk) {
357 		retval = -ENOMEM;
358 		goto out;
359 	}
360 
361 	if (out) {
362 		if (str_nums)
363 			for (i = 0; i < str_nums; i++)
364 				stream->out[str_list[i]].state =
365 						       SCTP_STREAM_CLOSED;
366 		else
367 			for (i = 0; i < stream->outcnt; i++)
368 				stream->out[i].state = SCTP_STREAM_CLOSED;
369 	}
370 
371 	asoc->strreset_chunk = chunk;
372 	sctp_chunk_hold(asoc->strreset_chunk);
373 
374 	retval = sctp_send_reconf(asoc, chunk);
375 	if (retval) {
376 		sctp_chunk_put(asoc->strreset_chunk);
377 		asoc->strreset_chunk = NULL;
378 		if (!out)
379 			goto out;
380 
381 		if (str_nums)
382 			for (i = 0; i < str_nums; i++)
383 				stream->out[str_list[i]].state =
384 						       SCTP_STREAM_OPEN;
385 		else
386 			for (i = 0; i < stream->outcnt; i++)
387 				stream->out[i].state = SCTP_STREAM_OPEN;
388 
389 		goto out;
390 	}
391 
392 	asoc->strreset_outstanding = out + in;
393 
394 out:
395 	return retval;
396 }
397 
398 int sctp_send_reset_assoc(struct sctp_association *asoc)
399 {
400 	struct sctp_stream *stream = &asoc->stream;
401 	struct sctp_chunk *chunk = NULL;
402 	int retval;
403 	__u16 i;
404 
405 	if (!asoc->peer.reconf_capable ||
406 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
407 		return -ENOPROTOOPT;
408 
409 	if (asoc->strreset_outstanding)
410 		return -EINPROGRESS;
411 
412 	if (!sctp_outq_is_empty(&asoc->outqueue))
413 		return -EAGAIN;
414 
415 	chunk = sctp_make_strreset_tsnreq(asoc);
416 	if (!chunk)
417 		return -ENOMEM;
418 
419 	/* Block further xmit of data until this request is completed */
420 	for (i = 0; i < stream->outcnt; i++)
421 		stream->out[i].state = SCTP_STREAM_CLOSED;
422 
423 	asoc->strreset_chunk = chunk;
424 	sctp_chunk_hold(asoc->strreset_chunk);
425 
426 	retval = sctp_send_reconf(asoc, chunk);
427 	if (retval) {
428 		sctp_chunk_put(asoc->strreset_chunk);
429 		asoc->strreset_chunk = NULL;
430 
431 		for (i = 0; i < stream->outcnt; i++)
432 			stream->out[i].state = SCTP_STREAM_OPEN;
433 
434 		return retval;
435 	}
436 
437 	asoc->strreset_outstanding = 1;
438 
439 	return 0;
440 }
441 
442 int sctp_send_add_streams(struct sctp_association *asoc,
443 			  struct sctp_add_streams *params)
444 {
445 	struct sctp_stream *stream = &asoc->stream;
446 	struct sctp_chunk *chunk = NULL;
447 	int retval;
448 	__u32 outcnt, incnt;
449 	__u16 out, in;
450 
451 	if (!asoc->peer.reconf_capable ||
452 	    !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
453 		retval = -ENOPROTOOPT;
454 		goto out;
455 	}
456 
457 	if (asoc->strreset_outstanding) {
458 		retval = -EINPROGRESS;
459 		goto out;
460 	}
461 
462 	out = params->sas_outstrms;
463 	in  = params->sas_instrms;
464 	outcnt = stream->outcnt + out;
465 	incnt = stream->incnt + in;
466 	if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
467 	    (!out && !in)) {
468 		retval = -EINVAL;
469 		goto out;
470 	}
471 
472 	if (out) {
473 		retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
474 		if (retval)
475 			goto out;
476 	}
477 
478 	chunk = sctp_make_strreset_addstrm(asoc, out, in);
479 	if (!chunk) {
480 		retval = -ENOMEM;
481 		goto out;
482 	}
483 
484 	asoc->strreset_chunk = chunk;
485 	sctp_chunk_hold(asoc->strreset_chunk);
486 
487 	retval = sctp_send_reconf(asoc, chunk);
488 	if (retval) {
489 		sctp_chunk_put(asoc->strreset_chunk);
490 		asoc->strreset_chunk = NULL;
491 		goto out;
492 	}
493 
494 	stream->incnt = incnt;
495 	stream->outcnt = outcnt;
496 
497 	asoc->strreset_outstanding = !!out + !!in;
498 
499 out:
500 	return retval;
501 }
502 
503 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
504 			struct sctp_association *asoc, __be32 resp_seq,
505 			__be16 type)
506 {
507 	struct sctp_chunk *chunk = asoc->strreset_chunk;
508 	struct sctp_reconf_chunk *hdr;
509 	union sctp_params param;
510 
511 	if (!chunk)
512 		return NULL;
513 
514 	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
515 	sctp_walk_params(param, hdr, params) {
516 		/* sctp_strreset_tsnreq is actually the basic structure
517 		 * of all stream reconf params, so it's safe to use it
518 		 * to access request_seq.
519 		 */
520 		struct sctp_strreset_tsnreq *req = param.v;
521 
522 		if ((!resp_seq || req->request_seq == resp_seq) &&
523 		    (!type || type == req->param_hdr.type))
524 			return param.v;
525 	}
526 
527 	return NULL;
528 }
529 
530 static void sctp_update_strreset_result(struct sctp_association *asoc,
531 					__u32 result)
532 {
533 	asoc->strreset_result[1] = asoc->strreset_result[0];
534 	asoc->strreset_result[0] = result;
535 }
536 
537 struct sctp_chunk *sctp_process_strreset_outreq(
538 				struct sctp_association *asoc,
539 				union sctp_params param,
540 				struct sctp_ulpevent **evp)
541 {
542 	struct sctp_strreset_outreq *outreq = param.v;
543 	struct sctp_stream *stream = &asoc->stream;
544 	__u32 result = SCTP_STRRESET_DENIED;
545 	__u16 i, nums, flags = 0;
546 	__be16 *str_p = NULL;
547 	__u32 request_seq;
548 
549 	request_seq = ntohl(outreq->request_seq);
550 
551 	if (ntohl(outreq->send_reset_at_tsn) >
552 	    sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
553 		result = SCTP_STRRESET_IN_PROGRESS;
554 		goto err;
555 	}
556 
557 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
558 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
559 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
560 		goto err;
561 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
562 		i = asoc->strreset_inseq - request_seq - 1;
563 		result = asoc->strreset_result[i];
564 		goto err;
565 	}
566 	asoc->strreset_inseq++;
567 
568 	/* Check strreset_enable after inseq inc, as sender cannot tell
569 	 * the peer doesn't enable strreset after receiving response with
570 	 * result denied, as well as to keep consistent with bsd.
571 	 */
572 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
573 		goto out;
574 
575 	if (asoc->strreset_chunk) {
576 		if (!sctp_chunk_lookup_strreset_param(
577 				asoc, outreq->response_seq,
578 				SCTP_PARAM_RESET_IN_REQUEST)) {
579 			/* same process with outstanding isn't 0 */
580 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
581 			goto out;
582 		}
583 
584 		asoc->strreset_outstanding--;
585 		asoc->strreset_outseq++;
586 
587 		if (!asoc->strreset_outstanding) {
588 			struct sctp_transport *t;
589 
590 			t = asoc->strreset_chunk->transport;
591 			if (del_timer(&t->reconf_timer))
592 				sctp_transport_put(t);
593 
594 			sctp_chunk_put(asoc->strreset_chunk);
595 			asoc->strreset_chunk = NULL;
596 		}
597 
598 		flags = SCTP_STREAM_RESET_INCOMING_SSN;
599 	}
600 
601 	nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
602 	if (nums) {
603 		str_p = outreq->list_of_streams;
604 		for (i = 0; i < nums; i++) {
605 			if (ntohs(str_p[i]) >= stream->incnt) {
606 				result = SCTP_STRRESET_ERR_WRONG_SSN;
607 				goto out;
608 			}
609 		}
610 
611 		for (i = 0; i < nums; i++)
612 			stream->in[ntohs(str_p[i])].mid = 0;
613 	} else {
614 		for (i = 0; i < stream->incnt; i++)
615 			stream->in[i].mid = 0;
616 	}
617 
618 	result = SCTP_STRRESET_PERFORMED;
619 
620 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
621 		flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
622 		GFP_ATOMIC);
623 
624 out:
625 	sctp_update_strreset_result(asoc, result);
626 err:
627 	return sctp_make_strreset_resp(asoc, result, request_seq);
628 }
629 
630 struct sctp_chunk *sctp_process_strreset_inreq(
631 				struct sctp_association *asoc,
632 				union sctp_params param,
633 				struct sctp_ulpevent **evp)
634 {
635 	struct sctp_strreset_inreq *inreq = param.v;
636 	struct sctp_stream *stream = &asoc->stream;
637 	__u32 result = SCTP_STRRESET_DENIED;
638 	struct sctp_chunk *chunk = NULL;
639 	__u32 request_seq;
640 	__u16 i, nums;
641 	__be16 *str_p;
642 
643 	request_seq = ntohl(inreq->request_seq);
644 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
645 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
646 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
647 		goto err;
648 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
649 		i = asoc->strreset_inseq - request_seq - 1;
650 		result = asoc->strreset_result[i];
651 		if (result == SCTP_STRRESET_PERFORMED)
652 			return NULL;
653 		goto err;
654 	}
655 	asoc->strreset_inseq++;
656 
657 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
658 		goto out;
659 
660 	if (asoc->strreset_outstanding) {
661 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
662 		goto out;
663 	}
664 
665 	nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
666 	str_p = inreq->list_of_streams;
667 	for (i = 0; i < nums; i++) {
668 		if (ntohs(str_p[i]) >= stream->outcnt) {
669 			result = SCTP_STRRESET_ERR_WRONG_SSN;
670 			goto out;
671 		}
672 	}
673 
674 	if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
675 		result = SCTP_STRRESET_IN_PROGRESS;
676 		asoc->strreset_inseq--;
677 		goto err;
678 	}
679 
680 	chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
681 	if (!chunk)
682 		goto out;
683 
684 	if (nums)
685 		for (i = 0; i < nums; i++)
686 			stream->out[ntohs(str_p[i])].state =
687 					       SCTP_STREAM_CLOSED;
688 	else
689 		for (i = 0; i < stream->outcnt; i++)
690 			stream->out[i].state = SCTP_STREAM_CLOSED;
691 
692 	asoc->strreset_chunk = chunk;
693 	asoc->strreset_outstanding = 1;
694 	sctp_chunk_hold(asoc->strreset_chunk);
695 
696 	result = SCTP_STRRESET_PERFORMED;
697 
698 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
699 		SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
700 
701 out:
702 	sctp_update_strreset_result(asoc, result);
703 err:
704 	if (!chunk)
705 		chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
706 
707 	return chunk;
708 }
709 
710 struct sctp_chunk *sctp_process_strreset_tsnreq(
711 				struct sctp_association *asoc,
712 				union sctp_params param,
713 				struct sctp_ulpevent **evp)
714 {
715 	__u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
716 	struct sctp_strreset_tsnreq *tsnreq = param.v;
717 	struct sctp_stream *stream = &asoc->stream;
718 	__u32 result = SCTP_STRRESET_DENIED;
719 	__u32 request_seq;
720 	__u16 i;
721 
722 	request_seq = ntohl(tsnreq->request_seq);
723 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
724 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
725 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
726 		goto err;
727 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
728 		i = asoc->strreset_inseq - request_seq - 1;
729 		result = asoc->strreset_result[i];
730 		if (result == SCTP_STRRESET_PERFORMED) {
731 			next_tsn = asoc->ctsn_ack_point + 1;
732 			init_tsn =
733 				sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
734 		}
735 		goto err;
736 	}
737 
738 	if (!sctp_outq_is_empty(&asoc->outqueue)) {
739 		result = SCTP_STRRESET_IN_PROGRESS;
740 		goto err;
741 	}
742 
743 	asoc->strreset_inseq++;
744 
745 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
746 		goto out;
747 
748 	if (asoc->strreset_outstanding) {
749 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
750 		goto out;
751 	}
752 
753 	/* G4: The same processing as though a FWD-TSN chunk (as defined in
754 	 *     [RFC3758]) with all streams affected and a new cumulative TSN
755 	 *     ACK of the Receiver's Next TSN minus 1 were received MUST be
756 	 *     performed.
757 	 */
758 	max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
759 	asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
760 
761 	/* G1: Compute an appropriate value for the Receiver's Next TSN -- the
762 	 *     TSN that the peer should use to send the next DATA chunk.  The
763 	 *     value SHOULD be the smallest TSN not acknowledged by the
764 	 *     receiver of the request plus 2^31.
765 	 */
766 	init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
767 	sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
768 			 init_tsn, GFP_ATOMIC);
769 
770 	/* G3: The same processing as though a SACK chunk with no gap report
771 	 *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
772 	 *     received MUST be performed.
773 	 */
774 	sctp_outq_free(&asoc->outqueue);
775 
776 	/* G2: Compute an appropriate value for the local endpoint's next TSN,
777 	 *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
778 	 *     chunk.  The value SHOULD be the highest TSN sent by the receiver
779 	 *     of the request plus 1.
780 	 */
781 	next_tsn = asoc->next_tsn;
782 	asoc->ctsn_ack_point = next_tsn - 1;
783 	asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
784 
785 	/* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
786 	 *      incoming and outgoing streams.
787 	 */
788 	for (i = 0; i < stream->outcnt; i++) {
789 		stream->out[i].mid = 0;
790 		stream->out[i].mid_uo = 0;
791 	}
792 	for (i = 0; i < stream->incnt; i++)
793 		stream->in[i].mid = 0;
794 
795 	result = SCTP_STRRESET_PERFORMED;
796 
797 	*evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
798 						    next_tsn, GFP_ATOMIC);
799 
800 out:
801 	sctp_update_strreset_result(asoc, result);
802 err:
803 	return sctp_make_strreset_tsnresp(asoc, result, request_seq,
804 					  next_tsn, init_tsn);
805 }
806 
807 struct sctp_chunk *sctp_process_strreset_addstrm_out(
808 				struct sctp_association *asoc,
809 				union sctp_params param,
810 				struct sctp_ulpevent **evp)
811 {
812 	struct sctp_strreset_addstrm *addstrm = param.v;
813 	struct sctp_stream *stream = &asoc->stream;
814 	__u32 result = SCTP_STRRESET_DENIED;
815 	__u32 request_seq, incnt;
816 	__u16 in, i;
817 
818 	request_seq = ntohl(addstrm->request_seq);
819 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
820 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
821 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
822 		goto err;
823 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
824 		i = asoc->strreset_inseq - request_seq - 1;
825 		result = asoc->strreset_result[i];
826 		goto err;
827 	}
828 	asoc->strreset_inseq++;
829 
830 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
831 		goto out;
832 
833 	if (asoc->strreset_chunk) {
834 		if (!sctp_chunk_lookup_strreset_param(
835 			asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
836 			/* same process with outstanding isn't 0 */
837 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
838 			goto out;
839 		}
840 
841 		asoc->strreset_outstanding--;
842 		asoc->strreset_outseq++;
843 
844 		if (!asoc->strreset_outstanding) {
845 			struct sctp_transport *t;
846 
847 			t = asoc->strreset_chunk->transport;
848 			if (del_timer(&t->reconf_timer))
849 				sctp_transport_put(t);
850 
851 			sctp_chunk_put(asoc->strreset_chunk);
852 			asoc->strreset_chunk = NULL;
853 		}
854 	}
855 
856 	in = ntohs(addstrm->number_of_streams);
857 	incnt = stream->incnt + in;
858 	if (!in || incnt > SCTP_MAX_STREAM)
859 		goto out;
860 
861 	if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
862 		goto out;
863 
864 	stream->incnt = incnt;
865 
866 	result = SCTP_STRRESET_PERFORMED;
867 
868 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
869 		0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
870 
871 out:
872 	sctp_update_strreset_result(asoc, result);
873 err:
874 	return sctp_make_strreset_resp(asoc, result, request_seq);
875 }
876 
877 struct sctp_chunk *sctp_process_strreset_addstrm_in(
878 				struct sctp_association *asoc,
879 				union sctp_params param,
880 				struct sctp_ulpevent **evp)
881 {
882 	struct sctp_strreset_addstrm *addstrm = param.v;
883 	struct sctp_stream *stream = &asoc->stream;
884 	__u32 result = SCTP_STRRESET_DENIED;
885 	struct sctp_chunk *chunk = NULL;
886 	__u32 request_seq, outcnt;
887 	__u16 out, i;
888 	int ret;
889 
890 	request_seq = ntohl(addstrm->request_seq);
891 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
892 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
893 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
894 		goto err;
895 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
896 		i = asoc->strreset_inseq - request_seq - 1;
897 		result = asoc->strreset_result[i];
898 		if (result == SCTP_STRRESET_PERFORMED)
899 			return NULL;
900 		goto err;
901 	}
902 	asoc->strreset_inseq++;
903 
904 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
905 		goto out;
906 
907 	if (asoc->strreset_outstanding) {
908 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
909 		goto out;
910 	}
911 
912 	out = ntohs(addstrm->number_of_streams);
913 	outcnt = stream->outcnt + out;
914 	if (!out || outcnt > SCTP_MAX_STREAM)
915 		goto out;
916 
917 	ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
918 	if (ret)
919 		goto out;
920 
921 	chunk = sctp_make_strreset_addstrm(asoc, out, 0);
922 	if (!chunk)
923 		goto out;
924 
925 	asoc->strreset_chunk = chunk;
926 	asoc->strreset_outstanding = 1;
927 	sctp_chunk_hold(asoc->strreset_chunk);
928 
929 	stream->outcnt = outcnt;
930 
931 	result = SCTP_STRRESET_PERFORMED;
932 
933 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
934 		0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC);
935 
936 out:
937 	sctp_update_strreset_result(asoc, result);
938 err:
939 	if (!chunk)
940 		chunk = sctp_make_strreset_resp(asoc, result, request_seq);
941 
942 	return chunk;
943 }
944 
945 struct sctp_chunk *sctp_process_strreset_resp(
946 				struct sctp_association *asoc,
947 				union sctp_params param,
948 				struct sctp_ulpevent **evp)
949 {
950 	struct sctp_stream *stream = &asoc->stream;
951 	struct sctp_strreset_resp *resp = param.v;
952 	struct sctp_transport *t;
953 	__u16 i, nums, flags = 0;
954 	struct sctp_paramhdr *req;
955 	__u32 result;
956 
957 	req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
958 	if (!req)
959 		return NULL;
960 
961 	result = ntohl(resp->result);
962 	if (result != SCTP_STRRESET_PERFORMED) {
963 		/* if in progress, do nothing but retransmit */
964 		if (result == SCTP_STRRESET_IN_PROGRESS)
965 			return NULL;
966 		else if (result == SCTP_STRRESET_DENIED)
967 			flags = SCTP_STREAM_RESET_DENIED;
968 		else
969 			flags = SCTP_STREAM_RESET_FAILED;
970 	}
971 
972 	if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
973 		struct sctp_strreset_outreq *outreq;
974 		__be16 *str_p;
975 
976 		outreq = (struct sctp_strreset_outreq *)req;
977 		str_p = outreq->list_of_streams;
978 		nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
979 		       sizeof(__u16);
980 
981 		if (result == SCTP_STRRESET_PERFORMED) {
982 			if (nums) {
983 				for (i = 0; i < nums; i++) {
984 					stream->out[ntohs(str_p[i])].mid = 0;
985 					stream->out[ntohs(str_p[i])].mid_uo = 0;
986 				}
987 			} else {
988 				for (i = 0; i < stream->outcnt; i++) {
989 					stream->out[i].mid = 0;
990 					stream->out[i].mid_uo = 0;
991 				}
992 			}
993 
994 			flags = SCTP_STREAM_RESET_OUTGOING_SSN;
995 		}
996 
997 		for (i = 0; i < stream->outcnt; i++)
998 			stream->out[i].state = SCTP_STREAM_OPEN;
999 
1000 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1001 			nums, str_p, GFP_ATOMIC);
1002 	} else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
1003 		struct sctp_strreset_inreq *inreq;
1004 		__be16 *str_p;
1005 
1006 		/* if the result is performed, it's impossible for inreq */
1007 		if (result == SCTP_STRRESET_PERFORMED)
1008 			return NULL;
1009 
1010 		inreq = (struct sctp_strreset_inreq *)req;
1011 		str_p = inreq->list_of_streams;
1012 		nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1013 		       sizeof(__u16);
1014 
1015 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1016 			nums, str_p, GFP_ATOMIC);
1017 	} else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1018 		struct sctp_strreset_resptsn *resptsn;
1019 		__u32 stsn, rtsn;
1020 
1021 		/* check for resptsn, as sctp_verify_reconf didn't do it*/
1022 		if (ntohs(param.p->length) != sizeof(*resptsn))
1023 			return NULL;
1024 
1025 		resptsn = (struct sctp_strreset_resptsn *)resp;
1026 		stsn = ntohl(resptsn->senders_next_tsn);
1027 		rtsn = ntohl(resptsn->receivers_next_tsn);
1028 
1029 		if (result == SCTP_STRRESET_PERFORMED) {
1030 			__u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1031 						&asoc->peer.tsn_map);
1032 			LIST_HEAD(temp);
1033 
1034 			asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1035 
1036 			sctp_tsnmap_init(&asoc->peer.tsn_map,
1037 					 SCTP_TSN_MAP_INITIAL,
1038 					 stsn, GFP_ATOMIC);
1039 
1040 			/* Clean up sacked and abandoned queues only. As the
1041 			 * out_chunk_list may not be empty, splice it to temp,
1042 			 * then get it back after sctp_outq_free is done.
1043 			 */
1044 			list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1045 			sctp_outq_free(&asoc->outqueue);
1046 			list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1047 
1048 			asoc->next_tsn = rtsn;
1049 			asoc->ctsn_ack_point = asoc->next_tsn - 1;
1050 			asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1051 
1052 			for (i = 0; i < stream->outcnt; i++) {
1053 				stream->out[i].mid = 0;
1054 				stream->out[i].mid_uo = 0;
1055 			}
1056 			for (i = 0; i < stream->incnt; i++)
1057 				stream->in[i].mid = 0;
1058 		}
1059 
1060 		for (i = 0; i < stream->outcnt; i++)
1061 			stream->out[i].state = SCTP_STREAM_OPEN;
1062 
1063 		*evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1064 			stsn, rtsn, GFP_ATOMIC);
1065 	} else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1066 		struct sctp_strreset_addstrm *addstrm;
1067 		__u16 number;
1068 
1069 		addstrm = (struct sctp_strreset_addstrm *)req;
1070 		nums = ntohs(addstrm->number_of_streams);
1071 		number = stream->outcnt - nums;
1072 
1073 		if (result == SCTP_STRRESET_PERFORMED)
1074 			for (i = number; i < stream->outcnt; i++)
1075 				stream->out[i].state = SCTP_STREAM_OPEN;
1076 		else
1077 			stream->outcnt = number;
1078 
1079 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1080 			0, nums, GFP_ATOMIC);
1081 	} else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1082 		struct sctp_strreset_addstrm *addstrm;
1083 
1084 		/* if the result is performed, it's impossible for addstrm in
1085 		 * request.
1086 		 */
1087 		if (result == SCTP_STRRESET_PERFORMED)
1088 			return NULL;
1089 
1090 		addstrm = (struct sctp_strreset_addstrm *)req;
1091 		nums = ntohs(addstrm->number_of_streams);
1092 
1093 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1094 			nums, 0, GFP_ATOMIC);
1095 	}
1096 
1097 	asoc->strreset_outstanding--;
1098 	asoc->strreset_outseq++;
1099 
1100 	/* remove everything for this reconf request */
1101 	if (!asoc->strreset_outstanding) {
1102 		t = asoc->strreset_chunk->transport;
1103 		if (del_timer(&t->reconf_timer))
1104 			sctp_transport_put(t);
1105 
1106 		sctp_chunk_put(asoc->strreset_chunk);
1107 		asoc->strreset_chunk = NULL;
1108 	}
1109 
1110 	return NULL;
1111 }
1112